We wish to invest between $14,000 and $18,500 on three different assets whose respective annual returns are 20.5%, 22%, and 21.5%. However, the amount investment on investment 2 should not exceed 25% of the total investment, and investments 1 and 2 should account for at least 50% of the total investment. We wish to use linear programming to maximize the annual return from the entire investment. Suppose that we have decided to increase our total maximum investment by $1000. How much should we expect this additional investment amount to contribute to the optimal return? Round your answer to the nearest whole number and do not include the dollar sign ($) with your answer. For example, "$2.56" should be entered as "3